U.S. Patent Application Publication No. 2002/0019507 discloses adhesive blends that can include a semi-crystalline copolymer of propylene and at least one comonomer selected from ethylene and at least one C4 to C20 alpha-olefin, wherein the copolymer has a weight average molecular weight (Mw) from about 15,000 to about 200,000, a melt index (MI) from about 7 dg/min to about 3000 dg/min, and a Mw/Mn of approximately 2. Also described are adhesive compositions having polymers or polymer blends with melt flow rates (MFRs) equal to and above 250 dg/min at 230° C.
Embodiments of the present invention may have one or more advantages over previously known materials, such as having an improved balance of elasticity, hysteresis properties, tensile modulus, and constant tensile modulus over a range of extensions.